Finding a solution to breaking gearcases on high power Rs

[Keira]

Effectively you only need 1st and 2nd gear to be straight cut... After that the car is moving so pressure on the casing is severely reduced... More energy is put to the wheels rather than through the casing...

Remember when the car is still the energy needs to go somewhere... No give on the clutch, no give on the wheels as you will have some decent rubber on etc... Its just for that split moment when the car is launched that the most energy causes the input shaft forward...

Although while the car is moving the hard accellerating will cause an amount of pressure on the casing but i think that re-enforcing the casing can work...

i've been saying for a while that with mine (when its finally built :roll: ) i have no intention of launching on full power, you can get the car launched well with 300odd bhp (markturbo's time proves that 8) ) once the cars moving i'll let all hell break loose :shock: :lol: :lol:. That should help to prevent any nasty casing failures along with other things being done. With a good boost controller and management that wont be a problem, like you say, its the initial sudden take up of drive that causes the casing to fail

 

[LOU ROB]

i've been saying for a while that with mine (when its finally built :roll: ) i have no intention of launching on full power, you can get the car launched well with 300odd bhp (markturbo's time proves that 8) ) once the cars moving i'll let all hell break loose :shock: :lol: :lol:. That should help to prevent any nasty casing failures along with other things being done. With a good boost controller and management that wont be a problem, like you say, its the initial sudden take up of drive that causes the casing to fail

Exactly my point all along 8) . These 6500rpm and side step the clutch crap DOESNT work :lol:
My quaiffe and os giken are spot on :shock:
And as you have also stated mate, is that you don't need big power to launch. My fastest 60' is 1.7 secs with circa 360bhp. now I have this spec, 1.9 secs is the best I can do. Knocking some duty out of first gear is the simplest way to do things.

 

[Keira]

And as you have also stated mate, is that you don't need big power to launch. My fastest 60' is 1.7 secs with circa 360bhp. now I have this spec, 1.9 secs is the best I can do. Knocking some duty out of first gear is the simplest way to do things.

despite what people may think i'm not as stupid as i look :lol:

we we're talking about it yesterday and the conclusion was 300-350bhp for 1st gear launching, then bring the power on progressively through the gears. You see it all the time, the lower powered cars driven properly always get nice clean launches with no fuss, the bigger power cars tend to spin the wheels until they get grip.

be interesting to see how you get on lou by lowering power in 1st gear 8) , if the appliance of science worked for zanussi it'll work for the pulsar

 

[GINGA]

we we're talking about it yesterday and the conclusion was 300-350bhp for 1st gear launching, then bring the power on progressively through the gears.

You won't be seeing anywhere near full power in the lower gears as theres just not enough load to get you anywhere near full boost, the problems you are having with the big power cars is that its a damn site harder to launch a car with a larger laggier turbo so you have to try that much harder to get it off the line cleanly
With a car with a smaller turbo its much easier to launch/control as its easier to keep it within its torque band 8)

 

[Keira]

didnt put that very well did i :lol: you're quite right 8) the car wont be making anywhere near that in the low gears :lol: What i meant is those sort of powered cars launch very cleanly 8)

damn site harder to launch a car with a larger laggier turbo so you have to try that much harder to get it off the line cleanly

one word

nitrous

2 words

progressive controller



Like you're saying you need to try harder to prevent a big-un bogging down, we'll have to see how lou gets on if he plays around with his set up

With my setup i wont need to rely on the turbo to get the car off the line, the original cunning plan of maxing out a smaller turbo then adding the gas has long gone and i'll now be doing what i originally said i didn't want to do :roll: :lol: :lol:

 

[GINGA]

I always found that 75hp of nitrous from a standing start worked wonders for not bogging down, clutch didn't like it much though :lol:

 

[LOU ROB]

Another way is to take some pre-load on the transmission when staged

 

[Keira]

do you launch off the handbrake lou ?

 

[LOU ROB]

I did a couple at brunters off the hand brake after I saw mo's box blow up.

I still need to do a few more to get it right

 

[Fire & skill]

it may be a stupid suggestion but is it possible to modify the st205 gt4 box to fit?

 

[Rishi]

Well even launch with launch control you will see anything from 1 - 1.6bar... 8)

Now at 1bar my turbo will make 400 - 500bhp... :shock:

So thats me screwed... :lol:

I'm going to just wait and see what Ian can come up with... Will speak to him about using either PPG or Quaife straight cut 1st and 2nd gears too...



Rishi

 

[Fast Guy]

How abit getting Quaiffe to look at making a thickwall casing :?:

 

[ram5ay]

Got an interesting thread for you's from the MazdaGTX Forum (as you prob know familia GTX/GTRs are pretty similar to the R and have similar gearbox probs when making good power), been checkin it out due to having one as my winter runabout and was impressed by this, if you get halfway through the thread you will find pics of a GTX with evo box and diffs used for rallying! If you can fit it to a 323 then hey

http://www.323gtx.co.uk/pn/index.ph...0&postorder=asc&highlight=evo+gearbox&start=0

 

[Rishi]

How abit getting Quaiffe to look at making a thickwall casing :?:

Because of the costs involved i doubt they would bother, but i will call them tomorrow just to see what they say...



Rishi

 

[Keira]

Got an interesting thread for you's from the MazdaGTX Forum (as you prob know familia GTX/GTRs are pretty similar to the R and have similar gearbox probs when making good power), been checkin it out due to having one as my winter runabout and was impressed by this, if you get halfway through the thread you will find pics of a GTX with evo box and diffs used for rallying! If you can fit it to a 323 then hey

the amount of works that gone into that car is amazing :shock:

when we were looking into it a while ago before si made up his brace the 323 came up The guy had killed numerous boxes but since fitting this little beasty all was aok 8)

its different to what you could do on the gtir but gave an idea of how to try to brace the gtir box,

As for fitting different boxes theres been an article in ppc that covers fitting different gearboxes to different engines, you need one that is very similar in input shaft position and drive shaft position then make up an adapter plate to get the bell housing on. Obviously theres more to it than that and with ours you've got the hassle of the transfer box added in but again it is another avenue to eventually explore 8) .

 

[celicaGT4st205]

it may be a stupid suggestion but is it possible to modify the st205 gt4 box to fit?

I believe Fensport run their cars on standard boxes. As for modifying and fitting, anything is possible with the money and know how.

 

[creedy]

is that a new end plate on thay 323 box?

 

[abyss]

it may be a stupid suggestion but is it possible to modify the st205 gt4 box to fit?

I believe Fensport run their cars on standard boxes. As for modifying and fitting, anything is possible with the money and know how.

GT4 boxes are good up to 500bhp are they not.

 

[ChrisS]

You won't be seeing anywhere near full power in the lower gears as theres just not enough load to get you anywhere near full boost, the problems you are having with the big power cars is that its a damn site harder to launch a car with a larger laggier turbo so you have to try that much harder to get it off the line cleanly

This is spot on. I could launch my old one with the standard turbo no probs. This one with the big turbo takes too much to get spooling in 1st, which until theres a proven way of keeping the casing in one piece im not prepared to do.

 

[ChrisS]

Posted: 27 Nov 2005 14:07 Post subject:

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I did a couple at brunters off the hand brake after I saw mo's box blow up.

I still need to do a few more to get it right

It'll be easier for you to do this on the strip lou as you've got that bit of role out that the timing gear didnt give you.